Getting up to speed with Air Sealing Details

Article 103 of the 2009 International Energy Conservation Code (IECC) requires that construction documents include air sealing details. Detailing the building envelope air barrier is a relatively recent challenge for architects, but it is a necessary task for communicating these fussy requirements to builders. The details of laps, connections, splices, and transitions of these thin membranes and tapes are especially important considering the potential downside of an unintended hole in an otherwise tight building envelope. With increased attention to energy conservation and air tightness of the building envelope, a small hole - like a pin hole in a balloon - can wreak havoc in terms of heat loss, vapor transmission, condensation, and moisture damage to construction materials that are concealed from view.

Some architects - already tuned in to our responsibility for construction drawings that show how building materials and products meet and connect with one another - have taken up this challenge by developing a sheet or sheets of details that show typical air sealing conditions that apply to their buildings. Instead of burying this information in other details where it may be hard to read due to the thinness of the air sealing materials, they have developed details specific to the air sealing materials, showing laps and transitions within the air barrier system and at transitions and terminations where the air barrier must connect with other building components like flashings, doors, and windows. Necessary details may include full-size views and exploded views to effectively show proper lapping and isometric views to effectively illustrate 3-dimensional shapes and connections. The details should be designed to effectively communicate the air sealing requirements.

Rethinking the Cost of Time

Building design and construction have been governed in modern history by our perception of time as a cost-based commodity. Both design and construction are assumed to have greater competitive value if production time is minimized. The first cost is generally lower if it takes less time to design and build a project. We can recognize an inverse relationship between first cost and long term cost when we consider building products (e.g., cheap windows vs. expensive windows), where lowest first cost may lead to higher long term costs in energy usage, maintenance, and replacement. Yet, as a profession and an industry, we have not been able or willing to recognize the long term value of time invested in design and construction, such that more available time (if well managed) results in more integrated attention to systems and details that enhance long term building performance and optimize long term operating costs. This issue is most notable in our continuing willingness to commit to abbreviated time periods for design and construction. We talk about the value of high performance buildings in terms of energy efficiency and healthful environments, yet the market continues to demand speed over performance due largely to the long established premise that "time is money" - a premise that is reinforced by the owner who wants the building quicker and by the designer and contractor who must bid low to get the job and then minimize time in order to avoid loss. When minimizing time is the highest priority, long term performance may suffer. Owners, designers, and contractors need to rethink the cost (and focus) of design and construction time as they relate to long term building performance. We have come to recognize long term risks associated with fast food; fast design and construction deserve similar consideration.

Breaking Ground with New Consultants

It can take a few projects to work out the communication kinks with a team of consultants. Consultants who have worked together and with the same team are likely to develop a good understanding of what to expect from other team members: learned and, perhaps, unwritten protocols about information exchange - what to expect and when, and what you have to request. A new consultant may bring both the promise of talent and the risk of problems related to communication. The challenge for both architects and consultants is to spend enough up-front time talking about who will do what and how and when information will be exchanged. It's better to consider your assumptions about what the other party will do and openly discuss details that may otherwise seem too mundane for review, especially if the scope of work is critical to timely project coordination and completion. While a formal consulting agreement may already be in place with an established scope of work and schedule, the details related to scope execution and coordination are not always covered in such an agreement.

Consultants bring not only different talents but also different ways of thinking, so it is best to reach an early understanding about the expectations of each party.

Interdisciplinary Coordination of Construction Documents

Gaps between design disciplines are a common cause of construction change orders. In some cases, the consulting disciplines' standard practices may generate a gap. For example, the electrical engineer may establish an electrical scope of work that "stops" 10 feet outside the building, while the site civil engineer may expect (and indicate on the site drawings) that the electrical contractor will provide power to a sewage lift station that is 15 feet outside the building. Unfortunately, it is quite possible that neither the electrical engineer nor the civil engineer will become aware of this gap in electrical service until the contractor submits an RFI.

Similar gaps can occur between plumbing and site trades, between mechanical and general building trades, between structural steel and miscellaneous metals trades, and between other trades. In most cases, proactive coordination by the project architect during the construction documents phase can help to minimize these gaps."Proactive" coordination means getting involved in finding and highlighting possible gaps and managing document revisions to eliminate the gaps by conferring with the related disciplines, considering applicable trade practices and regulations, and assigning responsibility to the most appropriate party. (It's usually not enough (and not really proactive) to simply tell the consultants to work it out between themselves.)

A Catch 22 Product Specification

Specifications occasionally include unintended contradictions, and in some instances they are related to schedule.

Not long ago, I reviewed a specification for roofing that included a requirement for a particular "ice and water shield" product and allowed no substitutions. The application requirements for the product included a minimum ambient temperature of 40 degrees F. That looked good from a quality control perspective, but the schedule for this fast-track, multi-building project in snow country required construction during the winter, when temperatures were expected to be well below 40 degrees F, and neither the schedule nor the budget allowed for temporary tenting and heating of whole buildings. As a result, in order to meet the schedule, the contractor had to apply the product under conditions that were not recommended by the manufacturer and were not in compliance with the specification.

Roof Design Basics for Snow Country

Leaks from ponds created by ice dams can frequently be traced to roof design. Roof designs that funnel snow to narrow spaces and narrow eaves are likely to promote the development of ice dams and resulting roof leaks. Roof designs with changing slopes that drain steep roofs to flatter roofs are likely to promote the development of ice in the area where the roof slopes meet. Standing seams of metal roofing can restrict snow runoff and promote the development of ice dams near the lower ends of valleys. Roof designs that include opportunities for warm interior air to reach the underside of the roof are likely to cause roof snow to melt and allow melt-water to run down and refreeze at the eaves, forming ice dams and leak-producing ponds behind the ice dams.

Some design principles to minimize the risk of ice dams and resulting leaks include the following:

1. Keep the roof design simple. Avoid complex roof architecture that requires runoff to change direction or follow circuitous paths to get off the roof. 
2. Avoid or minimize 'waterfall' conditions where runoff dripping from a high eave can freeze on a lower roof.
3. Avoid roof configurations that include a high, steep roof intersecting a lower, flatter roof surface.
4. Make way for snow. Remember that snow cannot get through tight spaces easily passed by water. Roof designs should allow wide paths for snow movement. Avoid tight dormer spacing, tight valleys, and other roof configurations that would restrict snow movement. 
5. Avoid standing seam configurations that restrict snow movement. Snow may move down-slope easily in a direction parallel to standing seams, but standing seams in valleys and roof slope changes can act like brakes, restricting snow movement toward eaves. Snow movement around chimneys and similar items can be restricted by standing seams, so special consideration should be given to a seam layout that will promote effective snow movement.
6. Keep the roof surface cold - especially up-slope from eaves - by keeping warm interior air away from the underside of the roof. Paths for interior air to reach the underside of the roof must be effectively blocked by a complete air barrier on the warm, interior side of the insulation (or by a properly installed, complete air barrier type of insulation).
7. Include support for underlayments, flashing, and roofing membranes at intersections between roof surfaces and related construction. Do not expect watertight integrity where a design calls for a dormer eave to intersect a main roof plan at a point without special construction to support underlayments, flashing, and roofing transitions.
8. Consider roof orientation and exposure when designing a roof. Snow will generally melt sooner on a roof exposed to sunlight than on a more shaded roof. As noted in 2 above, snow melt from an exposed roof can meet colder temperatures and refreeze as ice on the more shaded roof.
9. Minimize use of skylights and roof windows. Even the most energy efficient of these will melt snow that lands on them, and the melt-water is likely to refreeze as ice as it runs down on colder roof surfaces.
10. Do not expect an underlayment product like "ice and water shield" to compensate for design features that promote ice dams.
11. Consider the need for snow removal maintenance. Designs with features that promote ice dams may require frequent snow removal to minimize leaks.

Aesthetics and structural integrity are commonly the first considerations in roof design. Roof designs for snow country should also include basic considerations and accommodation of snow behavior in order to minimize problems caused by ice dams.

Bidders Trust Bid Documents for Take-off

Estimating quantities from a set of plans prepared by another architect reminds me that bidders are likely to rely on the accuracy of the drawings when preparing a take-off for a bid. If the drawings are inconsistent or include discrepancies, those are likely to affect the bids, and they may lead to claims of extra cost during construction, if the successful bidder determines that actual construction of the design requires more material (and related labor) than the drawings clearly indicated. The claims may be disputed as unreasonable based on a documented requirement for the bidder to consider the greatest quantity in the event of a discrepancy, but the limit of practicality may be exceeded where determination of actual quantity for bids would require exhaustive review and computation based on various plans and details. Bid preparation is typically limited to a short period of time due to a combination of the scheduled bid period and bidder attention. This is stated not for the purpose of blaming either the designer or the bidder but instead to suggest that accuracy in bid documents should be optimized in order to obtain accurate bids and to minimize discrepancies and the related disputes. There is an old saying that close bids are an indication of tight documents, meaning that the bidders all saw and bid the same scope. Of course, experience also shows that bids vary for reasons that have nothing to do with the bid documents, but that does not detract from the advantages of well coordinated bid documents.

Building Science and the Risks of Experimentation

Science is experimental; it consists of hypothesis and experiment. The path to success can be littered with experiments that fail. Scientists learn to expect failure along the way and to live with experimental failure as the cost of progress. Scientific design is experimental, and it is accompanied by an expected risk of failure.

The growing popularity of building science today brings increased risks of experimentation to the mainstreams of the building industry and the practice of architecture.

Historically, building design decisions were based on long established and proven practices and material selections. Expectations of reliability rested on proven performance over years or decades or - in some cases - centuries. The practice of experimentation was left mostly to the fringes and outliers. Main-streamers tended to avoid products and systems that lacked a good track record. Established building technology was a focus of learning and skill building; architects and builders could expect to learn from a previous generation and practice for decades with a building technology that would remain essentially the same.

More recently, we have seen and become obsessed with an increasing pace of change. Many equate faster with better, making decisions based on the latest available product or on predictions of the next invention or innovation - perhaps even with a belief that it must be better simply because it is new and not established. However, this kind of experimental approach to building design and construction dramatically increases the risk of building failures, in large part because it discredits time-tested performance and avoids or dismisses time-consuming consideration of the multiple roles played by building materials and the roles played by parties in the construction process.

Valid interest in (and popular incentives for) conservation and quality of resources and processes may have led to a willingness on the part of some to take more risks with experimentation. But questions need to be answered: Who assumes the risk? How much risk? Is there awareness and consent of assumed risk? and, If it fails, who owns the failure? Further, If it fails, how can it be considered a sustainable practice?

New Blog

Many of the posts from this blog have now been exported to a new blog: http://onthejobarchitect.blogspot.com/

Code Talk: Challenges for Architects

Most of the architects I have known are not comfortable with codes. They want to comply with applicable codes, but they find them confusing, tedious, contradictory, or even frightening. Codes are always being revised or superseded. It takes time to determine how a combination of applicable codes can be reasonably applied to a particular building type and scale, and it seems that the codes are changed almost as soon as the architect reaches a level of comfort with the requirements.

One of the reasons that it takes more than a little time to determine the application of codes to a specific project is that codes tend to be dense and voluminous texts that are full of "fine print", numerous exceptions and cross references, and hierarchies that are hard to follow (i.e., "Which article has precedence in this situation?"). Further, the architect is usually charged by statute with the professional responsibility to account for the application of numerous, differing codes - on the same project. In some cases, state or local authorities have adopted parts of different codes that cover similar matters, adding their own hierarchies to interpretation of requirements, and the architects are challenged with having to determine how to resolve gaps and conflicts that have not been addressed by the state or local authorities. Codes that include graphic illustrations of requirements are generally easier for architects to understand, because many - if not most - architects tend to think graphically. In that regard, accessibility guidelines that rely on graphic illustrations have been much easier to follow than text-only codes. Code commentaries or handbooks such as those available from ICC and NFPA can be more useful than the codes themselves due to the use of graphic illustrations. Graphic illustrations can also be enlightening for code writing authorities where the illustrations are intended to cover typical conditions, and the pictures themselves may raise questions that are then considered and addressed by the authorities.

Another challenge for architects is how to satisfy the professional responsibility to apply code requirements in those situations where less than full design services are contracted. If contracted services are limited to preliminary phases of design or other design iterations that exclude detailed drawings and specifications, how should the architect account for code requirements in the preliminary design phases, and how should the architect account for code requirements that would normally be applied to the development of detailed plans and specifications? How should the architect alert the owner (and/or contractor) of the need for the owner or contractor to complete the process of code compliance related to parts of the design that are beyond the architect's contracted scope of services?

I recall the advice or direction of one architect employer to make sure that what you do show on drawings is correct. His comment was not really focused on codes, but it could be applied to the question of code compliance in preliminary design. The code requirements to be considered in preliminary design tend to be large scale matters that would govern detailed development of a design in later phases. For example, a schematic design would consider zoning regulations such as building setbacks and building height and also allowable area and height as established by the applicable building code for the intended building use. That would be an appropriate design phase for consideration and documentation of building code construction type. The preliminary code analysis should reveal any applicable requirement for fire walls to divide the project into 'technically' separate buildings, and appropriate locations for such fire walls could be shown diagrammatically on the preliminary plans together with notation referencing the specific code provisions that would govern development of detailed design in a later phase. If it is not practical to even approximately locate such fire walls diagrammatically, those applicable code requirements should be included in notes that relate to the schematic plans. A similar approach can be followed for other code considerations that relate to the preliminary design, such as wheelchair accessible entrances that will require detailed design (e.g., accessible ramps, railings, door approaches, hardware, etc.) in subsequent design phases. Following this approach, each design phase would include code information appropriate to the phase and an indication of further design that is required in a subsequent phase.

One good reason to develop a comprehensive preliminary design approach to code compliance is to lay the groundwork for subsequent design development and documentation that will be performed by staff in the same office or on the same team. Another, perhaps more significant reason, is that architects are sometimes invited to defend themselves against claims of noncompliance where their services were limited to preliminary design and the code matters in question would customarily be applied to a later design phase (e.g., detailed construction documents). While an argument of exclusion by agreement may be valid, the time and cost to wage the argument after the fact may be a greater problem, especially if the project owner has encountered either an unexpected and costly construction change or post-construction change after the architect was dismissed from the project.

Change Orders: Making the Architect's Call on Contractor Claims

When construction contracts are based on drawings and specifications prepared by architects, the need for changes during construction raises questions about the completeness, correctness, and coordination of the architect’s drawings and specifications – in short, questions about the architect’s performance. Of course, change orders may also be precipitated by changes that are beyond the control of the architect, like changes in the project owner’s criteria for the project, or some changes in codes and regulations, or other conditions that were not foreseen or perhaps could not have been foreseen by either the owner or the architect.

Regardless of the actual causes of change orders, architects are commonly judged on the basis of “how many” change orders are executed on their projects. Simply quantifying the number of change orders on a project can be very misleading when it comes to gauging an architect’s performance. Given the possible sources of change orders cited above and also the fact that the architect does not have control over the number of change order requests or claims that a contractor may submit or the number of changes that a project owner may request or direct, it is easy to understand that the quantity of change orders is not an accurate way to measure an architect’s performance. Instead, it may be fairer – though still possibly an oversimplification - to consider the resulting cost of change orders that are related to errors, inconsistencies, and omissions in the drawings and specifications prepared by the architect and to compare the change order costs as a percentage of construction cost to those related to other architects’ drawings and specifications on similar projects that are designed and constructed under similar circumstances (i.e., measuring architects against their peers).

Considering the architect’s decisions in response to contractor claims, the American Institute of Architects (AIA) A-201 General Conditions (2007) include the following provision:

§ 4.2.12 Interpretations and decisions of the Architect will be consistent with the intent of, and reasonably inferable from, the Contract Documents and will be in writing or in the form of drawings. When making such interpretations and decisions, the Architect will endeavor to secure faithful performance by both Owner and Contractor, will not show partiality to either and will not be liable for results of interpretations or decisions rendered in good faith.

This requirement for impartiality is also found in AIA standard owner-architect agreements and in various professional regulations and codes of conduct. Yet, given that the architect is typically under contract with the owner and paid by the owner, the architect faces a de facto conflict of interest in evaluating a contractor’s claim for extra cost. Contractor claims are typically related to items of construction that are found to be needed but are not, at least in the contractor’s opinion, apparent on the drawings or in the specifications (“the contract documents”). The challenge for the architect faced with such a claim is to determine whether the needed item is “reasonably inferable” from the contract documents. If the architect determines that the item is required by the contract documents and denies the contractor’s claim, the owner may not have to pay an extra cost for the item, and the owner may be satisfied with the performance of the architect in terms of both the contract documents prepared by the architect and the construction administration services provided by the architect. If, on the other hand, the architect agrees with the contractor’s claim, then the owner may be dissatisfied with the architect on both counts. It takes a different owner attitude to appreciate the integrity that is necessary for the architect to acknowledge an imperfection in the contract documents.

There is no single rule of rightness that applies in every case. Sometimes one party is in the right, and sometimes the other party is in the right, and it is difficult to outline a simple rule for governing these situations beyond the provision of “impartiality” that is established in the General Conditions.

Drawings and specifications may never be perfect, and some would say they never can be perfect. However, drawings and specifications that are complete, consistent, coordinated, and are clear and readable to the extent possible leave less to interpretation; so there is less need for determinations of reasonable inference. With those goals in mind, change orders related strictly to imperfections in drawings and specifications can be minimized.

Another way to consider what is “reasonably inferable” is to ask what a bidder would see (or could reasonably be expected to see) in the contract documents as the basis of a bid (or sub-bid). The question of “inconsistencies” is interesting, because it is not clear that a bidder would actually see inconsistencies in the drawings and specifications that might become apparent to the architect when reviewing a contractor claim. The contractor may have developed a bid based on an interpretation (a complete “picture” of the project, if you will) that considers all of the differing provisions of the drawings and specifications in a consistent way. It is not unusual for the architect to be the one who is befuddled in this responsive review of the drawings and specifications, discovering “inconsistencies” that must now be interpreted in a way that would allow for compliance with a design intent that may not have been clearly conveyed. If it is necessary in the architect’s response to a contractor’s claim to explain numerous contradictions and take exceptions to numerous drawing and specification provisions in order to reach a conclusion that matches the designer’s intent, then the requirement is not reasonably inferable. A less troublesome approach for the architect would be to develop the necessary consistency in the drawings and specifications before they are issued for bidding.

Planning a Phased School Renovation and Expansion

School renovation and expansion projects are commonly related to overcrowding and/or obsolete facilities. Construction in phases may be the only choice when school operations must continue in the same building or on the same site during renovations and expansion. Phasing needs and requirements should be considered during the design of such a project in order to ensure that provisions are adequate for ongoing school operations during each phase of the project.

Phasing plans and specifications should be based on at least the following considerations:

1. Each phase should provide sufficient classroom space for the enrollment. It may be necessary or advisable to rent or purchase relocatable modular classroom units for use during one or more phases of the project. The actual determination of necessary classroom count should be made by the school authority.

2. Construction areas must be adequately separated from occupied areas.

a. Separation walls may include a combination of existing walls or partitions and temporary or permanent new construction that affords the required fire separation and minimizes dust, fumes, and noise transfer from construction areas to occupied areas[1]. It also, of course, must adequately separate construction personnel from building occupants.

b. Construction fencing should be planned to separate contractor staging and construction areas from owner/user areas, neighboring properties, and public areas (e.g., streets and sidewalks). The fencing layout may need to change from phase to phase.

3. Utilities should be adequate and uninterrupted[2] in the occupied areas of the building. These utilities would typically include heat, lights, power (normal and emergency systems), telecommunications, water, sewer, fire protection and alarm systems.

a. Replacing boilers in a school can take as long as six months, especially if hazardous materials removal is part of the process, so the heating season should be considered when determining project phasing and the feasibility of replacing a heating plant in the existing location. It may be more practical to construct a new boiler room in order to minimize downtime and the risk of delays.

b. In order to maintain existing electrical services, it may be necessary to build a new electrical service entrance and backfeed the existing systems that will continue to serve existing occupied areas[3]. These backfeeds may be different for each phase of a project.

c. Any of the utilities may need temporary connections, extensions, routes, “jumpers”, supports, and/or temporary equipment in order to satisfy the need for adequate and uninterrupted utilities in occupied areas[4].

4. Adequate exits (i.e., egress facilities) must be provided. Exits must be adequate in width and arrangement to meet applicable code requirements. Exit calculations should be performed to determine code compliance. If any existing exits will be blocked by a phase of construction, the remaining exits must be sufficient in arrangement and width to meet code requirements[5], or additional permanent or temporary exits must be provided. Exit signage and lighting must also be coordinated with the exit arrangement for a given phase. Temporary[6] corridors may be necessary to link occupied parts of a building that are separated by construction areas. Protected exit walkways may be necessary to link building exits to the public way and maintain separation from construction areas.

5. Toilet facilities must be adequate to serve the occupied areas of the building. In some cases, this may influence the delineation of phases or the location of new toilets.

6. The need for food service must be addressed throughout phased school construction. Food preparation, service, and dining areas may need to be relocated to accommodate renovation and/or new construction. The challenge is reduced if food is typically prepared in a remote facility and delivered to the school undergoing renovation, but the challenge may be greater if the school undergoing renovation houses the main kitchen for several schools in a district. Can a temporary source or provider be arranged to prepare and deliver adequate meals? And, if the cafeteria itself must be offline for renovation, can an alternative space be used?

7. Athletic facilities use tends to vary seasonally. It may be practical to take a gymnasium offline during the months when physical education and other athletic programs can be accommodated outside. This consideration may influence the phasing schedule such that gymnasium renovations occur during warmer months; and field improvements may need to be completed during summer vacations or planned such that new fields are completed before existing fields are improved or taken offline.

8. Parking must be maintained or provided in sufficient quantity and condition to serve the building occupants. The parking arrangement may need to be changed from phase to phase to satisfy the requirement. Walkways must be included to connect parking areas to building entrances. Parking areas for building users should be separate from construction parking areas.

9. Separate driveways should be planned for building users, school buses, and construction. The typically desirable separation of school buses from cars should be part of each phase, and a separate vehicle entrance to the site should be planned for construction personnel and deliveries.

10. Air intakes must be protected from dust and fumes. Temporary air intake “stacks” may be necessary at building air intakes adjacent to construction areas to avoid contaminants related to construction.

11. Accessibility features that are required for the school facilities must be maintained as part of each phase[7]. These would include, for example, ramps and elevators to the extent required.

Timely phasing considerations are likely to influence a project design in ways that will make construction less disruptive for building occupants.

The requirements related to phased construction should be clearly established on the drawings and in the specifications that will be used for bidding and constructing the project.

---

[1] Special requirements applicable to hazardous material removal may be more stringent and take precedence over general criteria based on desirable separation. Also, the EPA has published indoor air quality (IAQ) guidelines for school renovation (see http://www.epa.gov/iaq/schooldesign/renovation.html), and states and other authorities have established similar criteria.

[2] Contract documents may provide for necessary, brief or momentary interruptions to occur during power switchovers and similar changes. If they are necessary during occupied hours, they should be scheduled in advance with the building owner.

[3] Local fire authorities typically want to limit electrical services to a single location where power to an entire facility can be shut off in order, at least in part, to minimize risk to fire fighters.

[4] Special attention is warranted where partial building demolition will sever the services or structural support of services between occupied building areas. The bid documents should be clear in requiring temporary support or temporary rerouting of utilities and/or temporary equipment to serve the remote areas.

[5] The applicable code should be studied to determine whether any reduction in egress capacity is allowed, even in the case where existing exits exceed code requirements.

[6] The applicable code should be studied for requirements and limitations related to “temporary” construction. The duration of such construction may be limited by code to less than the anticipated duration of use during phased construction. For example, Section 108 of the 2009 IBC limits a permit for temporary structures and uses to 180 days; yet some requirements for temporary structures are not less than what is required for permanent construction. Chapter 31 of the 2009 IBC also includes requirements for temporary structures and for special construction that may be considered applicable to temporary facilities for phased school construction.

[7] Accessibility requirements would typically apply also to temporary modular classroom units.

A Few Predictors of Building Failure in New Construction

The following suggested predictors of building failure in new construction are based on years of experience tracing building failures to their causes. While the failures may express themselves as discrete detail flaws, underlying causes are often found in contractual decision making, project administration and management, and in conceptual design. The following predictors do not guarantee building failure, but they do indicate a heightened risk of failure.

1. Building from Schematic Design or other preliminary design documents – Schematic Design Drawings or other preliminary drawings that are prepared in CAD or a related computer program can appear quite precise, so it is possible to mistakenly expect such drawings to be sufficient for construction. Schematic Design Drawings typically lack sufficient detail for construction and may not be well conceived in terms of how materials and building components relate to one another. There is a high risk of building performance problems, including but not limited to building envelope leaks, when Schematic Drawings or other preliminary drawings are used as the basis of construction.
2. Eliminating or drastically limiting the Architect’s role during construction – If the Architect is dismissed from the construction phase of a project, or if the Architect’s services are reduced below the standard of practice in order to save cost or expedite construction, there is a heightened risk that changes and substitutions will be made without the review and scrutiny of the Architect, who would be expected to consider the compatibility of changes and substitutions with the design intent or even with code requirements and is expected to know more than contractors do about these matters. (Similar problems can occur if the Architect’s construction administration services are delegated to inexperienced staff, who may not have sufficient knowledge about the materials and systems they encounter on the construction site.)
3. Insufficient consideration of climate and weather – Success of building designs and design features in one climate are not good predictors of success in a different climate. This is true for building envelope designs in different geographic locations, and it is true for interior design features, materials, and details that are mistakenly used in exterior applications where they are inadequate for exposure to weather, including precipitation and exterior variations in temperature. It is also true for moisture sensitive interior materials that are subjected to high humidity related to building use (e.g., a swimming pool environment).
4. Assuming that the selection of an innovative, energy efficient product or system will, on its own, lead to a durable, energy efficient building – Examples include rot failures related to SIP (structural insulated panel) construction where panel joints were not properly sized and sealed and where OSB facing material was exposed to moisture in the belief (espoused by the panel manufacturer) that OSB was a waterproof material that need not be protected from moisture.

Certainly, there can be other predictors of building failure in new construction, and avoiding the predictors above may not lead to a trouble free building every time. Still, the issues above appear to be common enough to warrant their listing as predictors of building failure.

Planning for Concealed Site Conditions

Discovery of concealed site conditions can raise havoc with a project, possibly disrupting the construction schedule and adversely impacting the project budget. Here's a link to an article I wrote a few years ago to share some of my experience with concealed site conditions: Planning for Concealed Site Conditions

Delegating for Architects

Project results are directly related to the effectiveness of project communications. Successful delegation of responsibilities and tasks depends on effective communication. Download "Delegating for Architects" to read more about this.

Value Engineering

Any discussion of value engineering (V.E.) is likely to produce a rush of criticisms of the process if you work in an architecture or engineering practice. The architects and engineers are likely to recall bad experiences when V.E. was started late, approaching or following the completion of construction documents, at a time when the project schedule did not allow sufficient time to fully consider consequences and implement V.E. changes in a comprehensive and well coordinated manner. They are likely to complain that "V.E. stripped the value out of the project."

A better approach to V.E. is to start it earlier, when material and system decisions are being formulated and before a lot of time is invested in developing applicable details and specifications.

The Whole Building Design Guide (http://www.wbdg.org/resources/value_engineering.php) offers an excellent synopsis of V.E. and a clear picture of the advantages of doing it earlier in the life of a project.

"By Others" and "N.I.C."

The terms "By Others" and "Not In Contract" (or "N.I.C.") can add confusion to construction documents if the intent of the terms is not well established within the documents. The note "By Others" on a drawing may be intended to indicate that an item is to be provided by a different trade under the same overall construction contract, and "N.I.C." may be intended similarly to indicate an item that is to be provided by a different trade. However, these notes may have different meanings for different readers. Without further clarification, a general contractor seeing a note "By Others" or "N.I.C." may take it at face value to mean the item is not part of the general contractor's scope at all, even if the intent of the note was to indicate its exclusion only from the work of a particular trade or subtrade or a particular bid package. It is better to develop and use terms that convey the intent more precisely. For example, if an item shown on a site plan is intended to be provided by an electrical contractor whose work scope is also established on other drawings, it may be appropriate for the site plan to include the term "By Electrical Contractor" in a note relating to the item. Alternatively, it may be practical for all items that are not intended to be part of the site work to be noted "Not by Site Work Contractor", provided the term does not contradict a general contractor's contractual authority to assign such work. Drawings which are specifically intended to describe the work of a particular trade or subtrade can benefit from a List of Abbreviations or a List of Terms which clarify the meaning of such notes in order to minimize confusion.

Reviewing the Contractor's Application for Payment

On most public construction projects, the Architect reviews the Contractor's monthly Applications for Payment (a.k.a. "Requisitions") and certifies the amount to be paid to the Contractor for that month. If the Application is made on AIA Document G702, the front page includes the names of the Project, the Owner, the Contractor, and the Architect, an Application number, date(s) indicating the period covered by the Application, an overview accounting of the monetary status of the construction project, starting with the original contract sum and including a calculation of the Current Payment Due, considering change orders, the total amount completed and stored to date, Retainage to be withheld, and previous certificates for payment. The front page also includes a Change Order Summary, certification by the Contractor, conditions (terms) of certification by the Architect, and the amount certified. Continuation sheets should break down the contract sum and progress according to the approved Schedule of Values (see The Schedule of Values deserves close attention) and also include a detailed accounting of the status of work on approved Change Orders.

The Architect should review even the basic information on the front page before looking at the detailed information on the continuation sheets. It helps to have a copy of the previous month's Application in hand for comparison. Once you determine that the current month's Application is for the appropriate project (seriously), check the Original Contract Sum. In more than one instance, a contractor has changed the Original Contract Sum on an Application for Payment, resulting in an increase in payment without an approved Change Order. The Original Contract Sum should remain the same for the life of the Contract. Before turning to the continuation sheets, the Architect should apply the same scrutiny to the rest of the front page calculations and the wording of the certification. Different certification language may carry different liability.

Detailed information on the continuation sheets is typically generated as part of a "pencil requisition" process and in anticipation of work to be completed by the end of the month. The Architect needs to consider whether the final Application for the month represents work that was actually accomplished by the end of the month. If the Architect is aware that an anticipated material delivery did not occur, then the Architect should not certify payment for that. Likewise, if the Architect is aware that a specific work item was not completed, then the Architect should not certifiy payment as if the item had been completed. Necessary adjustments to the continuation sheets must be carried over to the front page and to the overall amount certified by the Architect for the period covered by the Application. It may be practical for the Contractor to make the necessary adjustments and then resubmit a corrected Application for the Architect's certification. If timely payment is an overriding concern, then the Architect may need to make the adjustments by annotating the Application, certifying a reduced amount, and notifying both the Owner and the Contractor of the reasons for the adjustments. (See also It takes timely money to make a project go )

Manage Design Costs with Early Project Overtime

One of Mike's PM tips for managing design costs on a project: "If you know you are going to have to work overtime on a project," he said, "do it in the beginning. It costs less to do overtime when there are only one or two people working on a project." (See Purposeful chaos (the 2-minute design offense))

This makes a lot of sense when considering a project on a compressed time line. If you're trying to figure out how to get all the work done in a short period of time, the least attractive alternative is having an army of designers and drafters burning the midnight oil and generating design questions as the completion deadline approaches. Eleventh hour overtime can quickly burn through budgeted hours and fee dollars, and too many new or unanswered questions at that stage can lead to unplanned chaos.

It's also interesting to consider how this principle of early overtime might benefit progress and labor costs on a construction site. Early trades - like earthwork, concrete, and steel - set the stage for a larger work force, and trades can multiply as the project becomes ready for their work.

Masonry Details, Toledo